Parsing XML with xgrep

Imagine this file.xml containing:

<vehicleinformation version="1.1" timestamp="1453323673">
  <vehicle locationX="4.336531" locationY="50.835707">Be.NMBS.P8401</vehicle>
  <stops number="9">
    <stop id="0" delay="16" canceled="0">
      <station id="BE.NMBS.008814001">Brussel-Zuid / Bruxelles-Midi</station>
      <time formatted="2016-01-20T17:06:00">1453305960</time>
      <platform normal="1">12</platform>
    </stop>
    <stop id="1" delay="18" canceled="0">
      <station id="BE.NMBS.008813003">Bru.-Centraal / Brux.-Central</station>
      <time formatted="2016-01-20T17:10:00">1453306200</time>
      <platform normal="1">3</platform></stop>
[...]

You can get the value of the delay in Brux.-Central (here 18 minutes) by specifying the XPath with the -x option, like this:

xgrep -x "/vehicleinformation/stops/stop[2]//@delay" file.xml

I use XPath Checker for Firefox to easily get the XPath.